QAPP
QAPP ANALYTICS · INTERACTIVE DEMO

Xbar–R

Monitor within-subgroup variation and process location separately, using limits established from a baseline period.

Your data

Two columns subgroup;value. Minimum 3 subgroups with the same number of measurements (2–10). Order of first appearance is the time order.

CSV/TXT without a header or pasted from Excel. Separator: semicolon or TAB; decimal separator: dot or comma. Maximum 200 observations in total, not 200 per group. Data is processed in the browser and is not uploaded to the server.

About the calculation

Read the R chart before the X̄ chart. Limits are estimated only from baseline subgroups; later subgroups are evaluated using those frozen limits.

Calculations run locally in the browser. Statistical distributions and functions use jStat 1.9.6; values are rounded only for display. For method selection, conditions of use and interpretation criteria, see the “Sources and methodological alignment” section above and any customer-specific requirements.

Ready for your data

Upload a dataset or use the example, then click “Calculate results”. Results will include charts, values and interpretation conditions.